The Dennis Lancet UF was a chassis for buses and coaches made by the British producer Dennis. It was built from 1959 to 1961 in limited numbers.

In the mid-1950s, Britain began a trend towards buses with underfloor mounted engines. The advantages of this arrangement were the larger seating capacity for a given length, the ease of entry and exit for passengers, better weight distribution and easier access to mechanical components, which resulted in savings of maintenance costs.

Dennis gave only the frame and the mechanicals, the buses were then provided with bodies from different body construction companies. This common design allowed a better adaptation to the needs of the operator. The buses were fitted with a diesel engine with a displacement of 7.5 litres with a power output of around 100 bhp. A manually-shifting five-speed transmission with switchable overdrive was used.

The coaches had a wheelbase of either 16 feet or 18 feet 4 inches. Alternatively a length of 30 feet and a width of 8 feet was ​​used.

With a curb weight of around 7 tons but they were relatively heavy for their time. The bodies of the coaches came from Duple Coachbuilders, Park Royal Vehicles and Plaxton. They were designed for 32 to 41 passengers and were characterised by a high set window line, deeply drawn windscreen and panoramic windows in the front and on the sides.